An introduction to the science & practice of photography (1888)
Jones, Chapman · London : Iliffe & Son · leaf 88
84 THE SCIENCE AND PRACTICE OF PHOTOGRAPHY. through a dense medium with non-parallel sides, the apparent displacement of the object is towards the thinner part of the interposed substance, because we cannot but imagine that the light entering our eyes has come in a straight line. In figure 10, B,… … Fjg. 10. shown, and the apparent displacement of an object viewed directly is indicated by the broken lines. If two prisms are placed base to base, light passing through them is concentrated, while if they are placed apex to apex the light is caused to diverge (figure 11). If Fig. 11. these two…
Photography
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